1. Field of the Invention
The invention relates to a pixel structure and a pixel structure having memorizing function. More particularly, the invention relates to a transflective pixel structure and a transflective pixel structure having memorizing function.
2. Description of Related Art
In current society, the development of multi-media technologies relies much on the progress of semiconductor devices or display apparatuses. As for displays, LCDs with advantages such as high definition, favorable space utilization, low power consumption and radiation-free operation have gradually become the mainstream of the market. Generally, the LCDs can be classified as transmissive LCDs, reflective LCDs, and transflective LCDs. The transflective LCDs can be used under either sufficient or insufficient illumination, and thus have a wide application scope.
The transflective LCD displays images by using a backlight source and an external light source simultaneously. Generally, the transflective LCD includes a pixel array substrate, an opposite substrate, and a liquid crystal layer sandwiched therebetween. A pixel structure disposed on the pixel array substrate has a transmittance region and a reflective region. Moreover, a transparent pixel electrode is disposed in the transmittance region and a reflective pixel electrode is disposed in the reflective region. The transparent pixel electrode is usually electrically connected to the reflective pixel electrode while the reflective pixel electrode is usually electrically connected to a drain through a contact opening disposed within an insulation layer in the reflective region. However, in conventional technique, in order to lower the power consumption when the LCD is not in operation, memory devices such as static random access memory (SRAM) are usually inserted into the reflective region of each pixel structure. Consequently, the utilizable space in the reflective region of the pixel structure is reduced. Thus, some devices of the transflective pixel structure need to be disposed in the transmittance region. However, it is important to ensure the pixel structure has sufficient transmittance and superior electrical property.